It has been recognized that reliably operating products benefit both the manufacturer and the manufacturer's customer who might be making a use of such products. In an attempt to improve product quality, various quality control schemes have been developed to attempt to design quality into respective products. For example, quality circles are a well known vehicle which has been used to promote product improvement. Alternately, the six sigma problem solving method has been widely used for the purpose of improving the quality of existing processes and products. The six sigma method which incorporates definitional, measurement, analysis improvement and control steps attempts to identify causes of quality defects and then addresses the defects and attempts to control process variables which are responsible for various defects.
While various known systems have definitely been instrumental in improving the quality of respective products, there continues to be an ongoing need for product improvement. Another aspect of quality improvement can be found in testing and analysis of the performance of existing products over at least portions of their expected life time.
From the point of view of a manufacturer wishing to improve product quality, it would be desirable to be able to systematically obtain representative samples of product from customers which have used the product for its intended purpose throughout a portion of the product's respective lifetime.
Evaluation of actual product from the field addresses known problems with laboratory testing which can be non-representative of real world performance. Additionally, testing of failed or defective product returned from the field may only identify atypical process failures as opposed to product design failures. Further, such testing may not be able to predict a mean time between failures for properly manufactured product.
Thus, it would be desirable to be able to conduct testing of a regular stream of product returned from customers where the returned product is not necessarily regarded as defective or nonperforming. Further, it would be desirable to be able to carry out testing and analysis of such product which might be received from a variety of different customers and which might have been exposed to differing operating conditions. Further, it would be desirable to be able to provide various levels of feedback to customers which were willing to exchange installed product for new replacement product as part of an ongoing improvement program.